Compositions and methods for screening therapeutic agents

Abstract

Methods and models for transporting agents across the blood brain barrier, the preparation of antibodies and antisense oligonucleotides, the preparation of experimental systems to study murine p97, the isolation of substances that modulate murine p97 expression and/or activity as well as the use of the murine p97 nucleic acid sequences and proteins and modulators thereof in diagnostic and therapeutic applications are described.

We claim:  
     
         1 . A method for screening a therapeutic agent for treating Alzheimer's disease (AD) comprising administering the agent to a mouse having an elevated level of mp97, and measuring the level of mp97 wherein a decrease in levels of mp97 indicates that the agent may be useful in treating Alzheimer's disease.  
     
     
         2 . A method according to  claim 1  wherein the level of mp97 is measured in the serum of the mouse.  
     
     
         3 . A method according to  claim 2  wherein the level of mp97 is measured using a radioimmunoassay, competitive assay or enzyme linked immunosorbant assay.  
     
     
         4 . A method for assessing the ability of an agent to cross the blood brain barrier comprising (1) administering an effective amount of (a) the agent associated with murine p97 or (b) the agent associated with a compound that binds murine p97 and (2) testing the levels of the agent in the nervous system.  
     
     
         5 . A method to assess the ability of a therapeutic agent to treat a neurological condition, comprising (1) administering to a mouse an effective amount of (a) the agent associated with murine p97 or (b) the agent associated with a compound that binds murine p97 and (2) monitoring the result of administration wherein an improvement in the neurological condition indicates that the agent has therapeutic effect.  
     
     
         6 . A method according to  claim 5  wherein the neurological condition is selected from the group consisting of cancers, neurodegenerative diseases, demyelinating diseases, amyotrophic lateral sclerosis, bacterial and viral infections, deficiency diseases, epilepsy, psychosis, pain and neurological disorders.  
     
     
         7 . A method according to  claim 5  wherein the neurological condition is Alzheimer's disease.  
     
     
         8 . A method for identifying a compound that affects murine p97 protein activity or expression comprising: 
 (a) incubating a test compound with a murine p97 protein or a nucleic acid encoding a murine p97 protein; and    (b) determining an amount of murine p97 protein activity or expression and comparing with a control wherein a change in the murine p97 protein activity or expression as compared to the control indicates that the test compound has an effect on murine p97 protein activity or expression.    
     
     
         9 . A method according to  claim 8  wherein the p97 is expressed in a cell.  
     
     
         10 . A method according to  claim 9  wherein the cell expresses p97 as a fusion protein with a reporter gene.  
     
     
         11 . A method of identifying substances which can bind with murine p97, comprising the steps of: 
 (a) reacting murine p97 and a test substance, under conditions which allow for formation of a complex between the murine p97 and the test substance, and    (b) assaying for complexes of murine p97 and the test substance, for free substance or for non complexed murine p97, wherein the presence of complexes indicates that the test substance is capable of binding murine p97.    
     
     
         12 . A method according to any one of  claims 1  to  11  wherein the p97 has an amino acid sequence shown in SEQ.ID.NO.: 2.  
     
     
         13 . A transgenic non-human animal having increased expression of p97.  
     
     
         14 . A transgenic non-human animal having decreased expression of p97.  
     
     
         15 . A transgenic animal according to  claim 13  or  14  wherein said animal is a mouse.  
     
     
         16 . A use of a transgenic naimal according to any one of  claims 13  to  15  to test therapeutic agents.  
     
     
         17 . A use according to  claim 16  to test therapeutic agents to treat neurological conditions.  
     
     
         18 . A use according to  claim 17  to test therapeutic agents to treat Alzheimer's disease.  
     
     
         19 . A substantially isolated mp97 protein having at least 80% sequence identity with the amino acid sequence of SEQ ID NO: 2.  
     
     
         20 . The substantially isolated mp97 protein of  claim 19  wherein the sequence identity is at least 90%.  
     
     
         21 . The substantially isolated mp97 protein of  claim 19  wherein the sequence identity is 100%.  
     
     
         22 . A substantially isolated mp97 protein having at least 80% sequence identity with amino acids 1 to 718 of SEQ ID NO: 2.  
     
     
         23 . The substantially isolated mp97 protein of  claim 22 , wherein the sequence identity is at least 90%.  
     
     
         24 . The substantially isolated mp97 protein of  claim 22 , wherein the sequence identity is 100%.  
     
     
         25 . A substantially isolated nucleic acid sequence encoding a mp97 protein wherein the mp97 protein has at least 80% sequence identity with SEQ ID NO: 1.  
     
     
         26 . A substantially isolated nucleic acid sequence encoding a mp97 protein wherein the mp97 protein has at least 90% sequence identity with SEQ ID NO: 1.  
     
     
         27 . A substantially isolated nucleic acid sequence encoding a mp97 protein wherein the mp97 protein has at least 80% sequence identity with SEQ ID NO: 1.  
     
     
         28 . An antibody that binds to a protein according to any one of  claims 19  to  24 .  
     
     
         29 . An antisense oligonucleotide that is complimentary to a nucleic acid sequence according to  claim 25  to  28 .